By default yes — a 48 kHz audio track in MKV becomes 48 kHz in M4A. If you need 44.1 kHz (CD-quality) for compatibility with older players, the advanced options include a sample-rate dropdown.
Audio extraction is much faster than video re-encoding — typically 5-15% of the source duration. A 1-hour MKV → M4A finishes in 3-9 minutes on the standard pipeline.
M4A formatek pelê deng e ku ji nêz ve bi MP4-ê ve girêdayî ye. Ew bi piştevaniya metadata re berhevkirina deng-kalîteya bilind pêşkêşî dike, ku wê ji bo serîlêdanên cihêreng maqûl dike.